A circuit board refers to an electrical insulating substrate printed with circuit patterns, and is used to mount electronic components.
The electronic components may include heat emitting devices, for example, LEDs (Light Emitting Diodes), and the heat emitting devices emit a significant amount of heat. The heat emitted from the heat emitting devices increases the temperature of the circuit board, thereby causing malfunction of the heat emitting devices and degrading the reliability of the heat emitting devices.
In order to solve the problem caused by the emitted heat, a radiant heat circuit board shown in FIG. 1 has been suggested.
FIG. 1 is a sectional view showing a conventional radiant heat circuit board 1. Referring to FIG. 1, the radiant heat circuit board 1 includes a metallic plate 2, an insulating layer 3, a circuit pattern 4, and a mounting part 5 for a heat emitting device.